[sdiy] fast-attack EGs and trigger sync

[Florian Anwander]

Hello Richard ,

> I'm told that a good click elimination trick with some patches is to 
> sync the VCOs to the envelope trigger pulse, so that the VCO cycle is 
> always locked to the start of the envelope.
The sync does reset to the start of the VCO-cycle, but it is not 
necessarily the through zero point. It resets to the start of the core 
waveform, either an saw or an triangle. If it is an saw, then the reset 
point is the vertical transition of the saw. If it is an triangle 
oscillator (like the CEM3340), then sync will reset to the top-(or 
bottom-)point fo the triangle.

In both cases this is not the point where a smooth zerocrossing happens, 
but it will reset to a maximum and cause a more or less welcome click.

If you choose another than the core waveform (e.g. quasi-sine), then the 
result may be even more "disturbing", because we won't hear a resetted 
sine, but we will hear what the waveform converter makes out of the 
resetted core waveform.

Florian